PREDICCTION OF THE CRITERIA OF SUCCESSFUL RADIOFREQUENCY CATHETER ABLATION OF ACCESSORY PATHWAYS

Abstract

RF catheter ablation is the first line of therapy in patients who have manifest APs particularly those with hemodynamic instability during arrhythmias and those who have poorly tolerated AVRT utilizing concealed AP as recommended by ACC/AHA/ESC practical guidelines (Blomstrom• Lundqvist et al, 2003). RF catheter ablation of APs has been demonstrated to be effective in the majority of patients with high primary successful rate exceeding 95% (Garcia Bolao and Brugada, 1998). Precise localization of an AP is an essential prerequisite for successful RF ablation because delivery of RF power causes discrete myocardial lesions. The purpose of the present study was to analyze and compare the local electrograms recorded at successful and unsuccessful sites of APs during RF catheter ablation in order to identify the criteria that may predict successful sites and minimize unnecessary RF delivery. This study was carried out by cooperation between the departments of cardiology, Assiut University and Ain Shams University. It included 43 patients (28 males & 15 females) who presented with symptomatic documented SVT. The pre-excited ECG was present in 24 patients (55.8%) while normal ECG was presentin ]9 patients (44.2%). They were referred for EPS and RF ablation. Their age ranged between 10 and 52 years with a mean of31.4 ±12.7 years. All patients underwent clinical evaluation, resting 12-lead ECG, echocardiographic examination and EPS for localization of the AP & confirmation_of its participation in patient's clinical tachycardia. They all underwent trials of RF ablation of their APs. All patients were followed up after one month for the clinical symptoms of recurrence and 12-leads ECG

for recurrence of manifest pre-excitation.